Giga-tronics 8003, Operation Manual

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Operation
Manual 20791, Rev. C, June 2001 2-5
Rear Panel Description
Refer to Figure 2-1 for the illustrations of the rear panel. The functions are described below.
I/O Connections
V
PROP
F In
The V
PROP
F input can be connected to a signal source with a voltage output (between -10 and
+10 Vdc) that is proportional to frequency. Then the measurement frequency is automatically
determined by the analyzer. This input is especially useful under swept measurement conditions.
Microwave power sensors have a measurable frequency response. That is, the detector produces slight
variations in I/O response with frequency. For this reason the frequency of operation should be entered
when performing measurements.
SWEEP In
This input receives the horizontal deflection voltage (between 0 and 10.75 Vdc) generated by the
sweeper to produce the proper positioning and trace information for the display. The circuitry is
designed so that if the voltage should exceed 10.75 V, the excess will be clipped and not cause any
damage.
BIAS Output
The bias output provides either biasing or operating voltage for some active external device. For
example, you might apply it to a pin diode on which you want to check the attenuation at various bias
levels, or it could be used to measure the input impedance on a modulator for which you are not sure.
The bias voltage is programmable from the front panel. It is generated by an internal amplified DAC in
the range of -10 to +10 Vdc with up to 150 mA current capacity. The circuitry is protected by self-
resetting, current-limiting devices (poly fuses). This means that if a short circuit should occur, the
output would just stop supplying current until the short was cleared and cool down time allowed. No
damage would be done.
AC Mod Output
The AC Mod Output modulates a sweeper when the scalar is operating in the ac mode. The output is
the same as the bias output with the same current limiting protection.
BLANKING Input
The Blanking Input interfaces with the source to receive a TTL signal for blanking band-change
switching points on multi-band sweepers.
INPUT 1 TTL Levels
The Input 1 TTL Levels connection provides the necessary synchronization to an internal log circuit of
the 8003 when used with certain sweepers. For example, if a synthesized sweeper is being used, the TTL
signal would tell the 8003 that the sweeper is locked, leveled, and that the signal was useful.
RESET Switch
This switch resets the 8003 to an initial power-on condition.
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